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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang yu Ao Shaofan Li Grace x.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics radial basis function Finite wing Deep learning neural network

Computation of Biobjective/Bidisciplinary Optimization

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Computation of Biobjective/Bidisciplinary Optimization

Nonstationary laser-supported ionization wave in layer of porous substance with subcritical density

第十一届全国计算流体力学会议

作者： Z.Q.Zhu H.Y.Fu r.x.yu H.M.Li Beijing University of Aeronautics and Astronautics. Beijing 100083China

1 Introduction It is well known that a modern fighter should have high aerodynamic performance, i.e., highlift (C) and low drag (C), high C/C at subsonic speed and low drag at supersonic speed, ***, stealthy performance has also become one of the basic requirements to a modern fighter. Sothe task of a designer today is to shape the aircraft with not only the maximum aerodynamic efficiencybut also a low observability. Up to now, reducing radar cross section (rCS) is the most importantpart of low observable technique for a flight vehicle. These requirements derive the development ofmultiobjective (MO)/multidisciplinary (MD) optimization. The goal of MO/MD optimization is toobtain one of the needed pareto solution at a minimum computing expense. A computational study ofbiobjective (BO)/bidisciplinary(BD) optimization of airfoils and wings is given in the present paper.

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Matter and radiation at Extremes 2024年第1期9卷 58-70页

作者： S.yu Gus’kov r.A.Yakhin P.N.Lebedev Physical Institute of russian Academy of Sciences Leninskii Prospect 53Moscow 119991Russia

A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced *** corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various *** solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore *** parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications.

关键词： laser pulse porous

DEM analysis of the influence of stirrer design on die filling with forced powder feeding

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Particuology 2024年第5期88卷 107-115页

作者： Chao Zheng Edward Yost Ariel r.Muliadi Nicolin Govender Ling Zhang Chuan-yu Wu School of Chemistry and Chemical Engineering University of SurreyGuildfordGU2 7XHUnited Kingdom Small Molecule Pharmaceutics GenentechInc.One DNA WaySouth San FranciscoCA94080USA

Die filling is a critical stage during powder compaction,which can significantly affect the product quality and *** this paper,a forced feeder is introduced attempting to improve the filling performance of a lab-scale die filling *** die filling process is analysed with a graphics processing units(GPU)enhanced discrete element method(DEM).Various stirrer designs are assessed for a wide range of process settings(i.e.,stirrer speed,filling speed)to explore their influence on the die filling performance of free-flowing *** results show that die filing with the novel helical-ribbon(i.e.,type D)stirrer design exhibits the highest filling ratio,implying that it is the most robust stirrer design for the feeder configuration ***,die filling performance with the type D stirrer design is a function of the stirrer speed and the filling speed.A positive variation of filling ratio(ηf>0%)can be ensured over the whole range of filling speed by adjusting the stirrer speed(i.e.,increasing the stirrer speed).The approach used in this study can not only help understand how the stirrer design affects the die filling performance but also guide the optimization of feeder system and process settings.

关键词： Discrete element method Die filling Forced feeding Stirrer design GPU computing

Identification of earthquake induced structural damage based on synchroextracting transform

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 475-487页

作者： roshan Kumar Gaurav Kumar Wei Zhao Arvind r Yadav Gang yu Jayendra Kumar Evans Amponsah Department of Electronic and Information Technology Miami College of Henan UniversityHenan 475004China Alliance University Alliance College of Engineering and DesignBanglore 562106India Department of Electronics and Comm Parul UniversityVadodra 391760India School of Electrical Engineering University of JinanJinan 250022China Department of Electronics and Comm NIT JamshedpurJamshedpur 831014India Department of Civil engineering Kwame Nkrumah University of Science and TechnologyKumasi 10959Ghana

Several popular time-frequency techniques,including the Wigner-Ville distribution,smoothed pseudo-Wigner-Ville distribution,wavelet transform,synchrosqueezing transform,Hilbert-Huang transform,and Gabor-Wigner transform,are investigated to determine how well they can identify damage to *** this work,a synchroextracting transform(SET)based on the short-time Fourier transform is proposed for estimating post-earthquake structural *** performance of SET for artificially generated signals and actual earthquake signals is examined with existing *** other tested techniques,SET improves frequency resolution to a great extent by lowering the influence of smearing along the time-frequency ***,interpretation and readability with the proposed method are improved,and small changes in the time-varying frequency characteristics of the damaged buildings are easily detected through the SET method.

关键词： cross-term damage detection earthquake signal synchroextracting transform time-frequency

U-Pb zircon geochronology of basaltic pyroclastic rocks from the basement beneath the xisha Islands in the northwestern South China Sea and its geological significance

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Acta Oceanologica Sinica 2024年第2期43卷 83-93页

作者： yu Zhang Kefu yu Shiying Li Guangxi Laboratory on the Study of Coral reefs in the South China Sea Guangxi UniversityNanning 530004China Coral reef research Center of China Guangxi UniversityNanning 530004China School of Marine Sciences Guangxi UniversityNanning 530004China Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of ScienceGuangzhou 510301China

As one of the micro-blocks dispersed in the South China Sea(SCS), the basement of the xisha Islands has rarely been drilled because of the thick overlying Cenozoic sediments, which has led to a confused understanding of the pre-Cenozoic basement of the xisha Islands. Well CK-1, a kilometer-scale major scientific drill in the xisha Islands in the northwestern SCS, penetrated thick reefal limestone(0–888.4 m) and the underlying basement rocks(888.4–901.4 m). In this study, we present the zircon U-Pb ages of basement basaltic pyroclastic rocks from Well CK-1 in the xisha Islands of the northwestern SCS to investigate the basement nature of the xisha microblock. The basement of Well CK-1 consists of basaltic pyroclastic rocks on the seamount. The zircon grains yielded apparent ages ranging from ca. 2 138.9 Ma to ca. 36 Ma. The old group of zircon grains from Well CK-1 was considered to be inherited zircons. Two Cenozoic zircons gave a weighted mean 206Pb/238U age of(36.3 ± 1.1) Ma,Mean Squared Weighted Deviations(MSWD) = 1.2, which may represent the maximum age of the volcano eruption. The Yanshanian inherited zircons(116.9–105.7 Ma and 146.1–130.2 Ma) from Well CK-1 are consistent with the zircons from Well xK-1, indicating that the basement of Chenhang Island may be similar to that of Well xK-1. We propose that the xisha micro-block may have developed on a uniform Late Jurassic metamorphic crystalline basement, intruded by Cretaceous granitic magma.

关键词： South China Sea xisha Islands basaltic pyroclastic rocks zircon

Design,synthesis,and biological evaluation of 1,2,4-triazole derivatives as potent antitubercular agents

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Chinese Chemical Letters 2024年第3期35卷 326-331页

作者： yu Wen Shichun Lun yuxue Jiao Wei Zhang Tianyu Hu Ting Liu Fan Yang Jie Tang Bing Zhang William r.Bishai Li-Fang yu Shanghai Engineering research Center of Molecular Therapeutics and New Drug Development School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Center for Tuberculosis research Department of MedicineDivision of Infectious DiseaseJohns Hopkins School of MedicineBaltimoreMD21231-1044United States Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Key Laboratory of Green Chemistry and Chemical Process School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China

Inhibition of mycobacterial membrane protein large 3(MmpL3)thereby affecting the mycolic acid biosynthetic pathway has been proven to be an effective strategy for developing antitubercular *** on the x-ray crystal structure of MmpL3 inhibitor complexes,a series of novel 1,2,4-triazole derivatives were designed,synthesized and evaluated antitubercular activity against Mtb strain *** structure–activity relationship exploration resulted in the identification of compounds 21 and 28,which possess potent antitubercular activity against Mtb strain H37rv[minimum inhibitory concentration(MIC)=0.03–0.13μg/mL]and the clinical isolates of multidrug resistance(MDr)and extensive drug resistance(xDr)tuberculosis(MIC=0.06–1.0μg/mL).Moreover,compounds 21 and 28 showed neglectable cytotoxicity(IC_(50)≥32μg/mL)to the mammalian Vero cells and favorable physicochemical and pharmacokinetic properties according to the in silico absorption,distribution,metabolism and excretion(ADME)***,the potential target of representative 1,2,4-triazole 28 was identified to be MmpL3 using a microscale thermophoresis(MST)assay.

关键词： Tuberculosis MDr and xDr-TB MmpL3 inhibitor 1 2 4-Triazole Structure-based drug design

Biotreatment of incinerated bottom ash and biocementation of sand blocks using soybean urease

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 36-46页

作者： xiaoniu yu Yidong xU Jiangsu Key Laboratory of Construction Materials Southeast UniversityNanjing211189China School of Civil Engineering and Architecture NingboTech UniversityNingbo315100China

Because of the high cost of cultivating urease-producing bacteria(UPB),this paper proposes soybean-urease-induced carbonate precipitation(SUICP)as a novel biocement for treatment of nickel contaminants and cementation of sandy *** found the optimal soaking time and soybean-powder content to be 30 min and 130 g/L,respectively,based on a standard of 5 U of urease *** most efficient removal of nickel ions is obtained with an ideal mass ratio of urea to nickel ions to soybean-powder filtrate(SPF)of 1:2.4:*** removal efficiency of nickel ions can reach 89.42%when treating 1 L of nickel-ion solution(1200 mg/L with the optimal mass ratio).In incinerated bottom ash(IBA),the removal efficiency of nickel ions is 99.33%with the optimal mass *** biocemented sandy soil,the average unconfined compressive strength(UCS)of sand blocks cemented with soybean urease-based biocement can reach 118.89 kPa when the cementation level is ***,the average content of CaCO_(3)in sand blocks is 2.52%.As a result,the SUICP process can be applied to remove heavy metal ions in wastewater or solid waste and improve the mechanical properties of soft soil foundations.

关键词： Biocement Soybean-powder filtrate(SPF) removal efficiency Sandy soil Unconfined compressive strength(UCS)

Heat Transfer Characteristics of a Microchannel Heat Sink with Highly-Dense Micro-Jet Arrays

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Journal of Thermal Science 2024年第3期33卷 1148-1160页

作者： ZHANG yu CHEN xiaoyan MIAO Lin CHEN Liang HOU yu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China Beijing Aerospace Technology Institute Beijing100083China

This paper proposed a new structure of highly-dense micro-jet arrays for hybrid jet-impingement/microchannel heat sinks(~120 jet per cm^(2) with jet width of 0.35 mm).Parametric study is performed to investigate the influence of structure and flow parameters on the convective heat transfer of water jet cooling in confined *** simulation results show that the optimal jet width,jet spacing and impingement distance are around 0.2 mm,0.2 mm and 0.3 mm,respectively,which can achieve a low thermal resistance as well as a relatively low pressure *** analysis of the heat transfer pathways shows that the micro-fin jet structures can extend the impinging heat transfer area and conduct a considerable proportion of heat,which can reach up to 38.9%with the reynolds number ranging from 797.1 to *** heat transfer characteristics in the heat sink will shift from impingement dominated heat transfer to the channel-convection dominated heat transfer as the jet impingement distance increases.A correlation is proposed to predict the average Nusselt number on the stagnation area for the heat sink with different structure parameters,and the deviations of predictions from the numerical results are less than 10%.

关键词： hybrid heat sink impingement microchannel thermal management high heat flux

The Enhanced Period Map and Equivariant Deformation Quantizations of Nilpotent Orbits

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Acta Mathematica Sinica,English Series 2024年第3期40卷 885-934页

作者： Shi Lin yu Department of Mathematics School of Mathematical SciencesXiamen UniversityXiamen 361005P.R.China

In a previous paper,the author and his collaborator studied the problem of lifting Hamil-tonian group actions on symplectic varieties and Lagrangian subvarieties to their graded deformation quantizations and apply the general results to coadjoint orbit method for semisimple Lie *** even quantizations were considered *** this paper,these results are generalized to the case of general quantizations with arbitrary *** key step is to introduce an enhanced version of the(truncated)period map defined by Bezrukavnikov and Kaledin for quantizations of any smooth sym-plectic variety x,with values in the space of Picard Lie algebroid over *** an application,we study quantizations of nilpotent orbits of real semisimple groups satisfying certain codimension condition.

关键词： Coadjoint orbit method deformation quantization Harish-Chandra modules semisimple Liegroups